CONTRIBUTIONS TO MAHASRI/AMY

Dr. Samarendra Karmakar

Director

Bangladesh Meteorological Department (BMD)

Introduction

•Scientists from Kyoto University under the leadership of Prof. T. Hyashi started observational experiments for monsoon in Bangladesh since 2004.

• Bangladesh Meteorological Department (BMD) extended all effort cooperation in these experiments.

• They also installed a number of Automatic rainfall measuring instruments and AWS (at two places) over Bangladesh under MAHASRI Project.

BAY OF BENGAL

INDIA

(Meghalaya)

INDIA(West Bengal)

INDIA(Tripura)

Dinajpur

Dhaka

MymensinghSylhet

Chittagong

Rajshahi

Locations of radar and raingauges

• AWS:☆– Dhaka(ICDDR,B)

• quasi-realtime• from 2004

– Cherrapunjee, Sylhet

• data logger• from 2007

• Raingauges– 6-gauges ：□– 12-gauges ：○– 5-gauges ：○– 15-gauges:○

Dhaka radar coverage

☆☆

☆

Prof. T. Hyashi’s Group and Bangladesh Meteorological Department’s Collaboration

Locations of Rain gauges in Bangladesh and India

6-RG’sBangladesh

5-RG’sMeghalaya

Data Coverage of RG’s and AWS’s

2007/032006/03

12-RG’sSylhet

15-RG’sAssam

2007/032006/03

2007/02AWS 2004/03

2007/022004/08

2007/032006/03

2006/03RADAR(Dhaka) 2007/03

new AWS

new AWS

How much is the world record?

26,461 mm @Cherrapunjee ( August 1860 – July 1861 )

9,360 mm @Cherrapunjee ( July 1861)

11,870 mm @Mawsynram

(greatest annual rainfall by Guinness record)

Annual rainfall in Cherrapunjee(1951-2003)

Border between Bangladesh and India 2006 May

Meghalaya Plateau

2004/07/29 2005/02/28 2007/06

2004/08/24 2005/03/04 2007/06

2005/03/01 2007/06

2004/08/01 2005/03/03 2007/06

2004/08/11 2005/03/01 2007/06

2004/08/05 2007/06

2004/03/03 2007/06Dhaka

AWS

Chittagong

Dhaka

Dinajpur

Mymensingh

Rajshahi

Sylhet

RGs

Obs. time table of Automatic Weather Stations and Rain Gauges

30 Jun.- no data

Rainfall Amount in 2006 Summer Monsoon

Netro Haor8,409mm

Chhatak8,685mm

Habiganj4,394mm

Amalshid

3,451mm

Analysis of data:Case study of pre-monsoon storm.

AWS– Diurnal variations

• -> 　Ｂ– AWS obs. case study.

• -> 　Ｃ

RADAR echo assoc. with tornadoes

meso-systemcaused tornadoes new AWS

Relation with water level at Surma river at Sylhet

Observations in 2007:

•Prof. Hyashi and his group made several RS observations during the Pre-monsoon and SW-monsoon months of April, May, June, July and 1st week of August 2007 at Dhaka Bangladesh.

•These upper air observations will very useful in the study of Nor’westers (severe thunderstorms)onset of monsoon, its ongoing activities and the conditions over Bangladesh during the formation and movement of monsoon depressions in the Bay of Bengal.

•The disturbances formed in the Bay of Bengal in 2007 are:

June: 2 Deep Depressions

July: 2 Well-marked lows

August: 3 Depressions.

•Radar Stations are at Dhaka, Rangpur, Cox’s

Bazar, Khepupara

•Cox’s Bazar was replaced by Doppler Radar in April 2007.

•Replacement of Khepupara Radar is in

progress and will be completed by March

2008.

•New Doppler Radar at Maulavibazar will be

commissioned by March 2009

Radars coverage of BMD

BMD has also taken up a project to establish 7 Agro-meteorological Observatories of BM D

in addition to existing 11 Agro-meteorological Observatories of

BMD has taken up a project to establish 5 new First Class Observatories in addition

to existing 35 First Class Observatories

Scientific Studies:

The upper air data obtained in 2007 will be analyzed to study:

•Onset of SW-monsoon over Bangladesh.

•Vertical distribution of moisture over Bangladesh.

Energetics of the troposphere over Bangladesh during the onset and on-going activities of monsoon.

•Precipitable water content of the troposphere and its correlation with actual rainfall.

•Fluxes of moisture and energy components in the troposphere over Bangladesh

In 2008, BMD will make RS observations at three stations: Dhaka, Chittagong and Bogra during the monsoon seasons. The surface observations (3 hrly) will be archived especially for the study of monsoon in 2008.

•These observational data will be analyzed to study the monsoon of 2008 and compared with the NWP products of NCMRWF and ECMRWF.

•The data obtained will be exchanged among the researchers.

THANK YOU